Activist investor Carl Icahn said he had initially tried to avoid a proxy fight against Forest Laboratories Inc and had offered to take at least two seats on the U.S. drugmaker's board, but he was rebuffed, leading to a battle that is becoming increasingly bitter and personal. Icahn, Forest's second-largest shareholder with a stake of about 10 percent, re-launched a proxy battle against the maker of the Lexapro antidepressant in recent months and has now nominated four directors for Forest's board, after losing a similar battle for board seats last year.